1. Field of the Invention
The present invention relates to a technique for collecting and recycling used or post-consumed bottles included in municipal waste received from home and industry, or collected from distributors.
2. Prior Art:
Reflecting the diversification in life style due to the abundance of materials, municipal waste discharged domestically and industrially has been constantly increasing, and all local governments are now facing a serious problem of how to take an effective and strong measure to achieve a quantitative reduction of waste materials as well as an effective recycling thereof. As a result of the "Law Concerning the Promotion of Recycling of Resources", classification of those post-consumed bottles collected and which amount to a large percentage of the waste material collected, has become an object of public attention as one of the important social needs. Municipal waste is delivered to the disposal department under the condition that pieces of broken glass such as those of post-consumed bottles, scraps of ferrous and non-ferrous materials, waste plastic, and waste papers are randomly mixed. The delivered waste is subject to classification into several patterns of materials, and a part of them worthy to be recycled is recovered as a raw material to be redissolved and recycled. Many attempts have been heretofore proposed and put into practical use as to the mentioned recycling stages, attention being mainly focussed on how to classify the waste materials with high efficiency. For example, Japanese Patent Publication (unexamined) No. Hei 4-354577 discloses a technique for separating post-consumed cans, post-consumed bottles, and post-consumed paper containers from one another within one case, and in which they are separately crushed.
Recently, in conformity with a strong administrative request from local governments in most municipalities, a way of classification by material is to be performed at the stage of collecting the waste materials on every family and, accordingly, a lot of techniques developed and directed exclusively to the classification of waste glass products have been also proposed. In recycling of glass products, one of the important aspects is a classification of the used glass products color by color because it is a requirement for improving recycling by redissolve post-consumed glass products of similar color.
For example, Japanese Patent Publication (unexamined) No. 5-96249 discloses a method for classifying small pieces of post-consumed glass (hereinafter with reference to this publication referred to as "cullet") by several color groups comprising the steps of detecting a color of a cullet by detecting the image of each cullet using a CCD camera while conveying the cullets on a belt conveyor and performing picture processing, sucking air by opening a specific suction port of a number of suction ports according to a signal from the picture processing provided on a classification drum disposed at one end of the conveyor, thus classifying cullets of specific color while dropping cullets of other colors by utilizing their weight.
To handle a large number of post-consumed bottles efficiently, it is strongly desired that a systematic and complete apparatus be constructed in addition to excellent individual classification techniques.
FIG. 15 shows the prior art apparatus disclosed in Japanese Patent Publication (unexamined) No. Sho 4-367774 comprising a classifying and vibrating screen 101 for classifying post-consumed bottles size by size, a feeder 102 for causing the classified post-consumed bottles to be in a row and in one direction, color sensors 103A to 103E for detecting the color of each of the fed post-consumed bottles, a dispenser 105 for delivering the post-consumed bottles classified color by color respectively to a disposal section (crushing section 104). Each of the color sensors has a function of detecting any one of transparent, brown, blue, green, and black colors of the post-consumed bottles conveyed on the belt conveyor, and upon identifying a color, a signal for actuating an electromagnetic switch is generated to transfer the bottle of specific color to a belt conveyor of the dispenser. As a result, as is described in this publication, the classification work of glass bottles conventionally conducted manually is automated, largely contributing to recycling of resources.
Post-consumed bottles are collected not only as a raw material classified color by color to be redissolved, but also to have them refilled. For this purpose, it has been heretofore customarily adopted that they be collected without defect and, after being subject to inspection, cleaning and sterilization, refilling them as new bottles. Particularly regarding alcoholic liquors, it is well-known business custom to sell alcoholic liquors and collect post-consumed bottles. However, the types of post-consumed bottles collected by alcoholic liquor dealers have been increasingly diversified recently. Such diversification including 1.8 l, 0.9 l, 0.54 l, 0.18 l, beer bottles of large, medium and small sizes, juice bottles of large and small sizes, ampoule bottles, etc. Since adoption of proper shape, size and color aiming at characteristic and discriminative goods, is an important prevailing business strategy actually, exact classification of the collected bottles type by type has become all the more difficult and complicated.
The mentioned prior art shown in FIG. 15 already faces a serious restriction when classifying by bottle size, if it is intended to recycle post-consumed bottles with their shapes as they are. That is, in the classification of post-consumed bottles size by size employing vibrating screens of various mesh sizes, it is quite difficult to exactly catch various shapes of post-consumed bottles by such a classification method. Accordingly, this prior art apparatus is not applicable, an apparatus for recycling the post-consumed bottles with their shapes as they are because of their excessively rough classification, though it may be useful for achieving a secondary object of conveyance for the classification by color on the condition that they are finally crushed. Also, a method for classifying various sizes of post-consumed bottles size by size with the use of vibration after inputting various sizes of post-consumed bottles all at once, an excessively large shock may be given to every bottle, whereby there is a high possibility of breaking or damaging the bottles. Thus, the prior art disclosed in the Japanese Patent Publication Hei 4-367774 is far from being applicable to the recycling of post-consumed bottles with their shapes as they are.
The prior art shown in FIG. 15 has a further disadvantage of requiring a very large installation space, since post-consumed bottles are classified size by size and each size is identified by passing them right under various color sensors in the course of a long conveyance, resulting in low detection efficiency and a classification performance of very low level.
Under such circumstances, one of the primary social needs now is that post-consumed bottles collected through alcoholic liquor dealers be generally accepted, and that many types of reusable bottles be efficiently classified and recycled as much as possible, while local governments use their utmost efforts for reducing the entire volume of waste materials. In other words, a system for easily and sufficiently satisfying the mentioned intricate and complicated needs is eagerly desired, particularly one usable on the actual working cite.